1. Field of the Invention
This invention relates to very high speed silver halide emulsions and to photographic films prepared therefrom. More particularly, this invention relates to compounds which can be used in these emulsions to reduce fog associated therewith.
2. Description of the Prior Art
There is a pressing need to reduce silver halide coating weights in order to reduce the cost of the photographic film produced therefrom. One way to accomplish this reduction is to increase the sensitivity of the emulsion in order to raise the speed of the film, and, simultaneously to reduce the size of the silver halide grain and thus increase the covering power of said film. The problem with this is that the addition of either extra sensitizing agent or the addition of new and more powerful sensitizers invites an increase of fog. While there is a veritable host of antifogging compounds in the prior art which are useful in conventional silver halide systems, there is still need to develop new and more powerful antifogging agents to overcome the problem noted above.
Therefore, it is an object of this invention to provide new, powerful antifoggants particularly useful in high speed, low coating-weight silver halide photographic film.